Subtract 8/7 from 30/81
1st number: 30/81, 2nd number: 1 1/7
30/81 - 8/7 is -146/189.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 7 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 81 × 7 = 567,
30/81 = 30 × 7/81 × 7 = 210/567 - Likewise, for the 2nd fraction, since 7 × 81 = 567,
8/7 = 8 × 81/7 × 81 = 648/567 - Subtract the two like fractions:
210/567 - 648/567 = 210 - 648/567 = -438/567 - After reducing the fraction, the answer is -146/189
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